Since man first began to use tobacco in smoke form, filtration of the same in order to reduce the pungent tars emitted therefrom as well as the tongue biting nicotine have been experimeted with. Filters have been used in conjunction with cigar and cigarette holders, have been built into the cigarettes themselves, and, of course, have been employed in pipe type smoking appliances.
Although the present invention obviously could be employed in cigar and cigarette type holders, reference herein will be made primarily to pipe type smoking apparatus.
Originally pipes were formed from clay and other materials with unimpeded bores through the stems thereof. To reduce the tar and nicotine build-up in the stems as well as the amount of such substances which was ingested by the smoker, various configured traps have been placed in the pipe stems so that the surfaces thereof could collect a portion of the tar and nicotine. Further, filters in the form of round tubular members for entrapment of nicotine and tar are commercially available under the brand name "Dr. Grabow" as well as others which fit specially designed pipes. Even the use of tobacco as a filter medium has been experimented with as has the use of entire filter type cigarettes as the filter medium.
Because of the peculiar configuration of smoking pipes, cigarette type filters alone are unsuitable because there is a great deal more tar and nicotine in the average pipe bowl of tobacco than in a single cigarette (which is what cigarette filters are, of course, designed for). Additionally, pipe smokers invariably reload their pipes and smoke several bowls before even considering changing the filter. When the pipe filter is finally changed, it is usually a major task since invariably the only reason it is done is that the filter and the entire stem has accumulated so much tar and nicotine that the pipe has become "too strong to smoke". When the pipe smoker is out in public, he does not usually want to expose other people to the messy, foul smelling pipe cleaners, the overloaded pipe filters and associated cleaning paraphernalia. Thus the average pipe smoker will often smoke his pipe well past the time when it should be cleaned and the filter changed.